The diploma thesis provides a detailed investigation of the hot deformation behavior of the EN AW-7049A aluminum alloy. EN AW-7049A belongs to the high-strength 7xxx series Al-Zn-Mg-Cu aluminum alloys. The aim of the research was to investigate the influence of temperature and strain rate on the mechanical behavior of the material and to determine the characteristics of its formability under hot deformation conditions relevant to the industrial application of these alloys.
The experimental work was carried out on a Gleeble 3500P thermomechanical simulator, where single-stage compression tests were performed. The compression tests were conducted in an inert atmosphere in order to reduce oxidation of the material during heating and deformation. The specimens were heated at a rate of 3 °C∙s⁻¹ to different deformation temperatures (300 °C, 350 °C, 400 °C and 450 °C) and were then isothermally held at the deformation temperature for 180 s. Deformation was performed at different strain rates in order to determine the viscoplastic response of the investigated alloy.
Based on force and displacement measurements, stress-strain curves (flow curves) were calculated. These curves enable the analysis of the mechanical behavior of the material during hot forming. The results showed that increasing the temperature reduces the flow stress and improves the formability of the material. It was also found that higher strain rates increase the flow stress.
Based on the obtained results, characteristic parameters of the behavior of the EN AW-7049A alloy during hot deformation were determined, providing an important basis for the optimization of industrial forming processes for 7xxx series aluminum alloys.
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